U.S. patent application number 15/126568 was filed with the patent office on 2017-03-23 for evaporation source for organic material.
The applicant listed for this patent is Applied Materials, Inc., Stefan BANGERT, Jose Manuel DIEGUEZ-CAMPO, Andreas LOPP, Uwe SCHUSSLER. Invention is credited to Stefan BANGERT, Jose Manuel DIEGUEZ-CAMPO, Andreas LOPP, Uwe SCHUSSLER.
Application Number | 20170081755 15/126568 |
Document ID | / |
Family ID | 50382443 |
Filed Date | 2017-03-23 |
United States Patent
Application |
20170081755 |
Kind Code |
A1 |
DIEGUEZ-CAMPO; Jose Manuel ;
et al. |
March 23, 2017 |
EVAPORATION SOURCE FOR ORGANIC MATERIAL
Abstract
An evaporation source array for depositing two or more organic
materials on a substrate is described. The evaporation source array
includes two or more evaporation crucibles, wherein the two or more
evaporation crucibles are configured to evaporate the two or more
organic materials, two or more distribution pipes with outlets
provided along the length of the two or more distribution pipes,
wherein a first distribution pipe of the two or more distribution
pipes is in fluid communication with a first evaporation crucible
of the two or more evaporation crucibles, two or more heat shields,
which surround the first distribution pipe, a cooling shield
arrangement provided at at least one side of the two or more
distribution pipes, wherein the at least one side is the side at
which the outlets are provided, and a cooling element provided at
or in the cooling shield arrangement for active cooling of the
cooling shield arrangement.
Inventors: |
DIEGUEZ-CAMPO; Jose Manuel;
(Hanau, DE) ; BANGERT; Stefan; (Steinau, DE)
; LOPP; Andreas; (Freigericht-Somborn, DE) ;
SCHUSSLER; Uwe; (Aschaffenburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DIEGUEZ-CAMPO; Jose Manuel
BANGERT; Stefan
LOPP; Andreas
SCHUSSLER; Uwe
Applied Materials, Inc. |
Hanau
Steinau
Freigericht-Somborn
Aschaffenburg
Santa Clara |
CA |
DE
DE
DE
DE
US |
|
|
Family ID: |
50382443 |
Appl. No.: |
15/126568 |
Filed: |
March 21, 2014 |
PCT Filed: |
March 21, 2014 |
PCT NO: |
PCT/EP2014/055744 |
371 Date: |
September 15, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 51/56 20130101;
C23C 14/042 20130101; H01L 51/001 20130101; H01L 51/0011 20130101;
C23C 14/243 20130101; C23C 14/56 20130101 |
International
Class: |
C23C 14/24 20060101
C23C014/24; H01L 51/00 20060101 H01L051/00; H01L 51/56 20060101
H01L051/56; C23C 14/04 20060101 C23C014/04; C23C 14/56 20060101
C23C014/56 |
Claims
1. An evaporation source array for depositing two or more organic
materials on a substrate, comprising: two or more evaporation
crucibles, wherein the two or more evaporation crucibles are
configured to evaporate the two or more organic materials; two or
more distribution pipes with outlets provided along the length of
the two or more distribution pipes, wherein a first distribution
pipe of the two or more distribution pipes is in fluid
communication with a first evaporation crucible of the two or more
evaporation crucibles; two or more heat shields, which surround the
first distribution pipe; a cooling shield arrangement provided on
at least one side of the two or more distribution pipes, wherein
the at least one side is the side at which the outlets are
provided; and a cooling element provided with the cooling shield
arrangement for active cooling of the cooling shield
arrangement.
2. The evaporation source array according to claim 1, wherein the
cooling shield arrangement comprises: a shaper shield arrangement,
which extends from the cooling shield arrangement in a direction of
vapor distribution, and which is configured to block a portion of
the two or more organic materials.
3. The evaporation source array according to claim 1, wherein the
cooling shield arrangement is provided on at least three sides of
the evaporation source array.
4. The evaporation source array according to claim 1, wherein the
first distribution shape has a cross-section perpendicular to the
length of the first distribution pipe, which is non-circular, and
which comprises: an outlet side at which the outlets are provided,
wherein the width of the outlet side of the cross-section is 30% or
less of the maximum dimension of the cross-section.
5. The evaporation source array according to claim 4, wherein the
cross-section perpendicular to the length of the distribution pipe
has a main section corresponding to a portion of a triangle.
6. The evaporation source array according to claim 1, wherein the
surface area of the two or more distribution pipes, at which the
outlets are provided, and which is defined by the surfaces of the
two or more distribution pipes, which are parallel+/-15.degree. to
a deposition area, is 30% or less of the surface area in a
projection of the two or more distribution pipes onto the
deposition area.
7. The evaporation source array according to claim 6, further
comprising: a first heating device configured for heating of the
first evaporation crucible; and a second heating device, which is
configured to be independently heated from the first heating
device, and being configured for heating the first distribution
pipe.
8. The evaporation source array according to claim 1, wherein the
two or more heat shields are spaced apart from each other by
protrusions or spots provided at or on at least one of the two or
more heat shields.
9. The evaporation source array according to claim 1, wherein the
one or more outlets are nozzles extending along an evaporation
direction.
10. The evaporation source array according to claim 9, wherein the
evaporation direction is horizontal.
11. The evaporation source array according to claim 1, wherein the
one or more outlets are nozzles extending along an evaporation
direction through the two or more heat shields.
12. The evaporation source array according to claim 1, further
comprising: an evaporator control housing configured to maintain
atmospheric pressure therein, wherein the evaporator control
housing is configured to house at least one element selected from
the group consisting of: a switch, a valve, a controller, a cooling
unit, a cooling control unit, a heating control unit, a power
supply, and a measurement device.
13. The evaporation source array according to claim 1, wherein the
distribution pipe comprises titanium or quartz.
14. The evaporation source array according to claim 1, wherein the
distribution pipe is a vapor distribution showerhead including the
one or more outlets.
15. The evaporation source array according to claim 1, wherein the
two or more distribution pipes are rotatable around an axis during
evaporation; and further comprising: one or more supports for the
two or more distribution pipes, wherein the one or more supports
are connectable to a first drive or includes the first drive,
wherein the first drive is configured for a translational movement
of the one or more supports and the two or more distribution
pipes.
16. The evaporation source array according to claim 3, wherein the
cooling shield arrangement is U-shaped.
17. The evaporation source array according to claim 2, wherein the
cooling shield arrangement is provided on the at least one side and
on the at least two further sides of the evaporation source
array.
18. The evaporation source array according to claim 17, wherein the
cooling shield arrangement is U-shaped.
19. The evaporation source array according to claim 5, wherein the
cross-section perpendicular to the length of the distribution pipe
is triangular with at least one of rounded corners and cut-off
corners.
20. The evaporation source array according to claim 14, wherein the
vapor distribution showerhead is a linear vapor distribution
showerhead providing a linear source for the organic material.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] Embodiments of the present invention relate to deposition of
organic material, a system for depositing materials, e.g. organic
materials, a source for organic material and deposition apparatuses
for organic material. Embodiments of the present invention
particularly relate to evaporation sources for organic material,
e.g. for evaporation apparatuses and/or manufacturing systems for
manufacturing devices, particularly devices including organic
materials therein and to evaporation source arrays for organic
material, e.g. for evaporation apparatuses and/or manufacturing
systems for manufacturing devices, particularly devices including
organic materials therein and to evaporation source arrays.
BACKGROUND OF THE INVENTION
[0002] Organic evaporators are a tool for the production of organic
light-emitting diodes (OLED). OLEDs are a special type of
light-emitting diodes in which the emissive layer comprises a
thin-film of certain organic compounds. Organic light emitting
diodes (OLEDs) are used in the manufacture of television screens,
computer monitors, mobile phones, other hand-held devices, etc.,
for displaying information. OLEDs can also be used for general
space illumination. The range of colors, brightness, and viewing
angle possible with OLED displays are greater than that of
traditional LCD displays because OLED pixels directly emit light
and do not require a back light. Therefore, the energy consumption
of OLED displays is considerably less than that of traditional LCD
displays. Further, the fact that OLEDs can be manufactured onto
flexible substrates results in further applications. A typical OLED
display, for example, may include layers of organic material
situated between two electrodes that are all deposited on a
substrate in a manner to form a matrix display panel having
individually energizable pixels. The OLED is generally placed
between two glass panels, and the edges of the glass panels are
sealed to encapsulate the OLED therein.
[0003] There are many challenges encountered in the manufacture of
such display devices. In one example, there are numerous labor
intensive steps necessary to encapsulate the OLED between the two
glass panels to prevent possible contamination of the device. In
another example, different sizes of display screens and thus glass
panels may require substantial reconfiguration of the process and
process hardware used to form the display devices. Generally, there
is a desire to manufacture OLED devices on large area
substrates.
[0004] One step in the manufacturing of large scale OLED displays,
which brings about various challenges, is the masking of the
substrate, e.g. for deposition of patterned layers. Further, known
systems typically have a small overall material utilization, e.g.
of <50%.
[0005] OLED displays or OLED lighting applications include a stack
of several organic materials, which are for example evaporated in
vacuum. The organic materials are deposited in a subsequent manner
through shadow masks. For the fabrication of OLED stacks with high
efficiency the co-deposition or co-evaporation of two or more
materials, e.g. host and dopant, leading to mixed/doped layers is
desired. Further, it has to be considered that there are
requirements for the evaporation of the very sensitive organic
materials.
[0006] For the production of e.g. OLED Displays, the pixelation of
the displays is achieved by depositing the organic material through
a shadow mask. To avoid a misalignment of the pixels caused by
thermal expansion of the mask induced through the heat load of the
evaporation source, shielding and/or cooling of the organic source
is desired.
[0007] Therefore, there is a continuous need for new and improved
systems, apparatuses and methods for forming devices such as OLED
display devices.
SUMMARY OF THE INVENTION
[0008] In light of the above, the evaporation source array
according to independent claim 1 is provided. Further advantages,
features, aspects and details are evident from the dependent
claims, the description and the drawings.
[0009] According to one embodiment, an evaporation source array for
depositing two or more organic materials on a substrate is
provided. The evaporation source array includes two or more
evaporation crucibles, wherein the two or more evaporation
crucibles are configured to evaporate the two or more organic
materials, two or more distribution pipes with outlets provided
along the length of the two or more distribution pipes, wherein a
first distribution pipe of the two or more distribution pipes is in
fluid communication with a first evaporation crucible of the two or
more evaporation crucibles, two or more heat shields, which
surround the first distribution pipe, a cooling shield arrangement
provided at at least one side of the two or more distribution
pipes, wherein the at least one side is the side at which the
outlets are provided, and a cooling element provided at or in the
cooling shield arrangement for active cooling of the cooling shield
arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] So that the manner in which the above recited features of
the present invention can be understood in detail, a more
particular description of the invention, briefly summarized above,
may be had by reference to embodiments. The accompanying drawings
relate to embodiments of the invention and are described in the
following:
[0011] FIG. 1 shows a schematic top view of a deposition apparatus
for depositing organic material in a vacuum chamber according to
embodiments described herein;
[0012] FIGS. 2A and 2B show schematic views of portions of an
evaporation source according to embodiments described herein;
[0013] FIG. 2C shows a schematic view of another evaporation source
according to embodiments described herein;
[0014] FIGS. 3A to 3C show schematic cross-sectional views of
portions of an evaporation source or an evaporation pipe,
respectively, according to embodiments described herein;
[0015] FIG. 4 shows a schematic cross-sectional view of a portion
of an evaporation source or an evaporation pipe, respectively,
according to embodiments described herein;
[0016] FIG. 5A shows a schematic view of a portion of an
evaporation pipe according to embodiments described herein;
[0017] FIGS. 5B and 5C show schematic views of portions of an array
of openings in shields according to embodiments described
herein;
[0018] FIG. 6 shows a schematic view of a portion of an evaporation
source according to embodiments described herein;
[0019] FIGS. 7A and 7B show schematic cross-sectional views of
portions of an evaporation source or an evaporation pipe,
respectively, according to embodiments described herein;
[0020] FIG. 8A shows a schematic view of another evaporation source
according to embodiments described herein;
[0021] FIG. 8B shows a schematic view of yet another evaporation
source according to embodiments described herein;
[0022] FIGS. 9A and 9B show schematic views of a deposition
apparatus for depositing organic material in a vacuum chamber
according to embodiments described herein and evaporation sources
for evaporation of organic material according to embodiments
described herein in different deposition positions in a vacuum
chamber; and
[0023] FIG. 10 shows a manufacturing system having a cluster system
portion, a vacuum swing module, a transfer chamber, a further
transfer chamber, a further vacuum swing module and a further
cluster system portion according to embodiments described
herein.
DETAILED DESCRIPTION OF EMBODIMENTS
[0024] Reference will now be made in detail to the various
embodiments of the invention, one or more examples of which are
illustrated in the figures. Within the following description of the
drawings, the same reference numbers refer to same components.
Generally, only the differences with respect to individual
embodiments are described. Each example is provided by way of
explanation of the invention and is not meant as a limitation of
the invention. Further, features illustrated or described as part
of one embodiment can be used on or in conjunction with other
embodiments to yield yet a further embodiment. It is intended that
the description includes such modifications and variations.
[0025] FIG. 1 shows an evaporation source 100 in a position in a
vacuum chamber 110. According to some embodiments, which can be
combined with other embodiments described herein, the evaporation
source is configured for a translational movement and a rotation
around an axis. The evaporation source 100 has one or more
evaporation crucibles 104 and one or more distribution pipes 106.
Two evaporation crucibles and two distribution pipes are shown in
FIG. 1. The distribution pipes 106 are supported by the support
102. Further, according to some embodiments, the evaporation
crucibles 104 can also be supported by the support 102. Two
substrates 121 are provided in the vacuum chamber 110. Typically, a
mask 132 for masking of the layer deposition on the substrate can
be provided between the substrate and the evaporation source 100.
Organic material is evaporated from the distribution pipes 106.
[0026] According to embodiments described herein, the substrates
are coated with organic material in an essentially vertical
position. That is the view shown in FIG. 1 is a top view of an
apparatus including the evaporation source 100. Typically, the
distribution pipe is a vapor distribution showerhead, particularly
a linear vapor distribution showerhead. Thereby, the distribution
pipe provides a line source extending essentially vertically.
According to embodiments described herein, which can be combined
with other embodiments described herein, essentially vertically is
understood particularly when referring to the substrate
orientation, to allow for a deviation from the vertical direction
of 20.degree. or below, e.g. of 10.degree. or below. This deviation
can be provided for example because a substrate support with some
deviation from the vertical orientation might result in a more
stable substrate position. Yet, the substrate orientation during
deposition of the organic material is considered essentially
vertical, which is considered different from the horizontal
substrate orientation. The surface of the substrates is thereby
coated by a line source extending in one direction corresponding to
one substrate dimension and a translational movement along the
other direction corresponding to the other substrate dimension.
[0027] FIG. 1 illustrates an embodiment of a deposition apparatus
200 for depositing organic material in a vacuum chamber 110. The
evaporation source 100 is provided in the vacuum chamber 110 on a
track, e.g. a looped track (as shown in FIG. 9A) or linear guide
220. The track or the linear guide 220 is configured for the
translational movement of the evaporation source 100. Thereby,
according to different embodiments, which can be combined with
other embodiments described herein, a drive for the translational
movement can be provided in the evaporation source 100, at the
track or linear guide 220, within the vacuum chamber 110 or a
combination thereof. FIG. 1 shows a valve 205, for example a gate
valve. The valve 205 allows for a vacuum seal to an adjacent vacuum
chamber (not shown in FIG. 1). The valve can be opened for
transport of a substrate 121 or a mask 132 into the vacuum chamber
110 or out of the vacuum chamber 110.
[0028] According to some embodiments, which can be combined with
other embodiments described herein, a further vacuum chamber, such
as maintenance vacuum chamber 210 is provided adjacent to the
vacuum chamber 110. Thereby the vacuum chamber 110 and the
maintenance vacuum chamber 210 are connected with a valve 207. The
valve 207 is configured for opening and closing a vacuum seal
between the vacuum chamber 110 and the maintenance vacuum chamber
210. The evaporation source 100 can be transferred to the
maintenance vacuum chamber 210 while the valve 207 is in an open
state. Thereafter, the valve can be closed to provide a vacuum seal
between the vacuum chamber 110 and the maintenance vacuum chamber
210. If the valve 207 is closed, the maintenance vacuum chamber 210
can be vented and opened for maintenance of the evaporation source
100 without breaking the vacuum in the vacuum chamber 110.
[0029] Two substrates 121 are supported on respective
transportation tracks within the vacuum chamber 110. Further, two
tracks for providing masks 132 thereon are provided. Thereby,
coating of the substrates 121 can be masked by respective masks
132. According to typical embodiments, the masks 132, i.e. a first
mask 132 corresponding to a first substrate 121 and a second mask
132 corresponding to a second substrate 121, are provided in a mask
frame 131 to hold the mask 132 in a predetermined position.
[0030] According to some embodiments, which can be combined with
other embodiments described herein, a substrate 121 can be
supported by a substrate support 126, which is connected to an
alignment unit 112. An alignment unit 112 can adjust the position
of the substrate 121 with respect to the mask 132. FIG. 1
illustrates an embodiment where the substrate support 126 is
connected to an alignment unit 112. Accordingly, the substrate is
moved relative to the mask 132 in order to provide for a proper
alignment between the substrate and the mask during deposition of
the organic material. According to a further embodiment, which can
be combined with other embodiments described herein, alternatively
or additionally the mask 132 and/or the mask frame 131 holding the
mask 132 can be connected to the alignment unit 112. Thereby,
either the mask can be positioned relative to the substrate 121 or
the mask 132 and the substrate 121 can both be positioned relative
to each other. The alignment units 112, which are configured for
adjusting the position between a substrate 121 and a mask 132
relative to each other, allow for a proper alignment of the masking
during the deposition process, which is beneficial for high quality
or LED display manufacturing.
[0031] Examples of an alignment of a mask and a substrate relative
to each other include alignment units, which allow for a relative
alignment in at least two directions defining a plane, which is
essentially parallel to the plane of the substrate and the plane of
the mask. For example, an alignment can at least be conducted in an
x-direction and a y-direction, i.e. two Cartesian directions
defining the above-described parallel plane. Typically, the mask
and the substrate can be essentially parallel to each other.
Specifically, the alignment can further be conducted in a direction
essentially perpendicular to the plane of the substrate and the
plane of the mask. Thus, an alignment unit is configured at least
for an X-Y-alignment, and specifically for an X-Y-Z-alignment of
the mask and the substrate relative to each other. One specific
example, which can be combined with other embodiments described
herein, is to align the substrate in x-direction, y-direction and
z-direction to a mask, which can be held stationary in the vacuum
chamber 110.
[0032] As shown in FIG. 1, the linear guide 220 provides a
direction of the translational movement of the evaporation source
100. On both sides of the evaporation source 100 a mask 132 is
provided. The masks 132 can thereby extend essentially parallel to
the direction of the translational movement. Further, the
substrates 121 at the opposing sides of the evaporation source 100
can also extend essentially parallel to the direction of the
translational movement. According to typical embodiments, a
substrate 121 can be moved into the vacuum chamber 110 and out of
the vacuum chamber 110 through valve 205. Thereby, a deposition
apparatus 200 can include a respective transportation track for
transportation of each of the substrates 121. For example, the
transportation track can extend parallel to the substrate position
shown in FIG. 1 and into and out of the vacuum chamber 110.
[0033] Typically, further tracks are provided for supporting the
mask frames 131 and thereby the masks 132. Accordingly, some
embodiments, which can be combined with other embodiments described
herein, can include four tracks within the vacuum chamber 110. In
order to move one of the masks 132 out of the chamber, for example
for cleaning of the mask, the mask frame 131 and, thereby, the mask
can be moved onto the transportation track of the substrate 121.
The respective mask frame can then exit or enter the vacuum chamber
110 on the transportation track for the substrate. Even though it
would be possible to provide a separate transportation track into
and out of the vacuum chamber 110 for the mask frames 131, the
costs of ownership of a deposition apparatus 200 can be reduced if
only two tracks, i.e. transportation tracks for a substrate, extend
into and out of the vacuum chamber 110 and, in addition, the mask
frames 131 can be moved onto a respective one of the transportation
tracks for the substrate by an appropriate actuator or robot.
[0034] FIG. 1 illustrates an exemplary embodiment of the
evaporation source 100. The evaporation source 100 includes a
support 102. The support 102 is configured for the translational
movement along the linear guide 220. The support 102 supports two
evaporation crucibles 104 and two distribution pipes 106 provided
over the evaporation crucible 104. Thereby, the vapor generated in
the evaporation crucible can move upwardly and out of the one or
more outlets of the distribution pipe. According to embodiments
described herein, the distribution pipe 106 can also be considered
a vapor distribution showerhead, for example a linear vapor
distribution showerhead.
[0035] According to embodiments described herein, an evaporation
source includes one or more evaporation crucibles and one or more
distribution pipes, wherein a respective one of the one or more
distribution pipes can be in fluid communication with the
respective one of the one or more evaporation crucibles. Various
applications for OLED device manufacturing include processing
steps, wherein two or more organic materials are evaporated
simultaneously. Accordingly, as for example shown in FIG. 1, two
distribution pipes and corresponding evaporation crucibles can be
provided next to each other. Accordingly, the evaporation source
100 may also be referred to as an evaporation source array, e.g.
wherein more than one kind of organic material is evaporated at the
same time. As described herein, the evaporation source array itself
can be referred to as an evaporation source for two or more organic
materials.
[0036] The one or more outlets of the distribution pipe can be one
or more openings or one or more nozzles, which can, e.g., be
provided in a showerhead or another vapor distribution system. The
evaporation source can include a vapor distribution showerhead,
e.g. a linear vapor distribution showerhead having a plurality of
nozzles or openings. A showerhead can be understood herein, to
include an enclosure having openings such that the pressure in the
showerhead is higher than that outside of the showerhead, for
example by at least one order of magnitude.
[0037] According to embodiments described herein, which can be
combined with other embodiments described herein, the rotation of
the distribution pipe can be provided by a rotation of an
evaporator control housing, on which at least the distribution pipe
is mounted. Additionally or alternatively, the rotation of the
distribution pipe can be provided by moving the evaporation source
along the curved portion off a looped track (see, for example, FIG.
9A). Typically, also the evaporation crucible is mounted on the
evaporator control housing. Accordingly, the evaporation sources
include a distribution pipe and an evaporation crucible, which may
both, i.e. together, rotatably mounted.
[0038] According to embodiments described herein, evaporation
sources for organic materials or evaporation source arrays,
respectively, can be improved with respect to at least two desires,
which may be provided independently from one another or in
combination. Firstly, evaporation sources evaporating one or more
organic materials may suffer from an insufficient mixture of the
organic materials when depositing the two or more organic materials
on a substrate. Accordingly, it is desirable to improve mixing of
organic materials for applications, for which, for example, two
different organic materials are deposited to provide one organic
layer on a substrate. A corresponding application can, for example,
be deposition of a doped layer, wherein a host and one or more
dopants are provided. Secondly, as exemplarily described with
respect to FIG. 1, many applications require masking of the
substrate during deposition of organic material. In light of the
fact that the masking step typically requires high precision, a
thermal expansion of the mask needs to be reduced. Embodiments
described herein, allow for an improved temperature stability of
the mask and/or a reduced heat load at the position of the mask,
which may be generated by an evaporation source.
[0039] According to some embodiments, which can be combined with
other embodiments described herein, the evaporation source includes
a distribution pipe (e.g. an evaporation tube). The distribution
pipe may have a plurality of openings, such as an implemented
nozzle array. Further, the evaporation source includes a crucible,
which contains the evaporation material. According to some
embodiments, which can be combined with other embodiments described
herein, the distribution pipe or evaporation tube can be designed
in a triangular shape, so that it is possible to bring the openings
or the nozzle arrays as close as possible to each other. This
allows for achieving an improved mixture of the different organic
materials, e.g. for the case of the co-evaporation of two, three or
even more different organic materials.
[0040] According to yet further embodiments, which can additionally
or alternatively be implemented, evaporation sources described
herein allow for temperature variation at the position of the mask,
which can be, for example, below 5 Kelvin, or even below 1 K. The
reduction of the heat transfer from evaporation source to the mask
can be provided by an improved cooling. Additionally or
alternatively, in light of the triangular shape of the evaporation
source, the area, which radiates towards the mask, is reduced.
Additionally, a stack of metal plates, for example up to 10 metal
plates, can be provided to reduce the heat transfer from the
evaporation source to the mask. According to some embodiments,
which can be combined with other embodiments described herein, the
heat shields or metal plates can be provided with orifices for the
outlet or nozzles and may be attached to at least the front side of
the source, i.e. the side facing the substrate.
[0041] FIGS. 2A to 2C show portions of an evaporation source
according to embodiments described herein. An evaporation source
can include a distribution pipe 106 and an evaporation crucible 104
as shown in FIG. 2A. Thereby, for example, the distribution pipe
can be an elongated cube with heating unit 715. The evaporation
crucible can be a reservoir for the organic material to be
evaporated with a heating unit 725. According to typical
embodiments, which can be combined with other embodiments described
herein, distribution pipe 106 provides a line source. For example,
a plurality of openings and/or outlets, such as nozzles, are
arranged along at least one line. According to an alternative
embodiment, one elongated opening extending along the at least one
line can be provided. For example, the elongated opening can be a
slit. According to some embodiments, which can be combined with
other embodiments described herein, the line extends essentially
vertically. For example, the length of the distribution pipe 106
corresponds at least to the height of the substrate to be deposited
in the deposition apparatus. In many cases, the length of the
distribution pipe 106 will be longer than the height of the
substrate to be deposited, at least by 10% or even 20%. Thereby, a
uniform deposition at the upper end of the substrate and/or the
lower end of the substrate can be provided.
[0042] According to some embodiments, which can be combined with
other embodiments described herein, the length of the distribution
pipe can be 1.3 m or above, for example 2.5 m or above. According
to one configuration, as shown in FIG. 2A, the evaporation crucible
104 is provided at the lower end of the distribution pipe 106. The
organic material is evaporated in the evaporation crucible 104. The
vapor of organic material enters the distribution pipe 106 at the
bottom of the distribution pipe and is guided essentially sideways
through the plurality of openings in the distribution pipe, e.g.
towards an essentially vertical substrate.
[0043] According to some embodiments, which can be combined with
other embodiments described herein, the outlets (e.g. nozzles) are
arranged to have a main evaporation direction to be
horizontal+-20.degree.. According to some specific embodiments, the
evaporation direction can be oriented slightly upward, e.g. to be
in a range from horizontal to 15.degree. upward, such as 3.degree.
to 7.degree. upward. Correspondingly, the substrate can be slightly
inclined to be substantially perpendicular to the evaporation
direction. Thereby, undesired particle generation can be reduced.
For illustrative purposes, the evaporation crucible 104 and the
distribution pipe 106 are shown without heat shields in FIG. 2A.
Thereby, the heating unit 715 and the heating unit 725 can be seen
in the schematic perspective view shown in FIG. 2A.
[0044] FIG. 2B shows an enlarged schematic view of a portion of the
evaporation source, wherein the distribution pipe 106 is connected
to the evaporation crucible 104. A flange unit 703 is provided,
which is configured to provide a connection between the evaporation
crucible 104 and the distribution pipe 106. For example the
evaporation crucible and the distribution pipe are provided as
separate units, which can be separated and connected or assembled
at the flange unit, e.g. for operation of the evaporation
source.
[0045] The distribution pipe 106 has an inner hollow space 710. A
heating unit 715 is provided to heat the distribution pipe.
Accordingly, the distribution pipe 106 can be heated to a
temperature such that the vapor of the organic material, which is
provided by the evaporation crucible 104, does not condense at an
inner portion of the wall of the distribution pipe 106. Two or more
heat shields 717 are provided around the tube of the distribution
pipe 106. The heat shields are configured to reflect heat energy
provided by the heating unit 715 back towards the hollow space 710.
Thereby, the energy required to heat the distribution pipe, i.e.
the energy provided to the heating unit 715, can be reduced because
the heat shields 717 reduce heat losses. Further, heat transfer to
other distribution pipes and/or to the mask or substrate can be
reduced. According to some embodiments, which can be combined with
other embodiments described herein the heat shields 717 can include
two or more heat shield layers, e.g. five or more heat shield
layers, such as ten heat shield layers.
[0046] Typically, as shown in FIG. 2B, the heat shields 717 include
openings at positions of the opening or outlet 712 in the
distribution pipe 106. The enlarged view of the evaporation source
shown in FIG. 2B shows four openings or outlet 712. The openings or
outlets 712 can be provided along one or more lines, which are
essentially parallel to the axis of the distribution pipe 106. As
described herein, the distribution pipe 106 can be provided as a
linear distribution showerhead, for example, having a plurality of
openings disposed therein. Thereby, a showerhead as understood
herein has an enclosure, hollow space, or pipe, in which the
material can be provided or guided, for example from the
evaporation crucible. The showerhead can have a plurality of
openings (or an elongated slit) such that the pressure within the
showerhead is higher than outside of the showerhead. For example,
the pressure within the showerhead can be at least one order of
magnitude higher than that outside of the showerhead.
[0047] During operation, the distribution pipe 106 is connected to
the evaporation crucible 104 at the flange unit 703. The
evaporation crucible 104 is configured to receive the organic
material to be evaporated and to evaporate the organic material.
FIG. 2B shows a cross-section through the housing of the
evaporation crucible 104. A refill opening is provided, for
example, at an upper portion of the evaporation crucible, which can
be closed using a plug 722, a lid, a cover or the like for closing
the enclosure of evaporation crucible 104.
[0048] An outer heating unit 725 is provided within the enclosure
of the evaporation crucible 104. The outer heating element can
extend at least along a portion of the wall of the evaporation
crucible 104. According to some embodiments, which can be combined
with other embodiments described herein, one or more central
heating elements 726 can additionally or alternatively be provided.
FIG. 2B shows two central heating elements 726. The central heating
elements 726 can include conductors 729 for providing electrical
power to the central heating elements. According to some
implementations, the evaporation crucible 104 can further include a
shield 727. The shield 727 can be configured to reflect heat
energy, which is provided by the outer heating unit 725 and, if
present, the central heating elements 726, back into the enclosure
of the evaporation crucible 104. Thereby, efficient heating of the
organic material within the evaporation crucible 104 can be
provided.
[0049] According to some embodiments, which have been described
herein, heat shields such as shield 717 and shield 727 can be
provided for the evaporation source. The heat shields can reduce
energy loss from the evaporation source. Thereby, energy
consumption can be reduced. However, as a further aspect,
particularly for deposition of organic materials, heat radiation
originating from the evaporation source can be reduced,
particularly heat radiation towards the mask and the substrate
during deposition. Particularly for deposition of organic materials
on masked substrates, and even more for display manufacturing, the
temperature of the substrate and the mask needs to be precisely
controlled. Thus, heat radiation originating from the evaporation
source can be reduced or avoided. Accordingly, some embodiments
described herein include heat shields such as shield 717 and shield
727.
[0050] These shields can include several shielding layers to reduce
the heat radiation to the outside of the evaporation source. As a
further option, the heat shields may include shielding layers,
which are actively cooled by a fluid, such as air, nitrogen, water
or other appropriate cooling fluids. According to yet further
embodiments, which can be combined with other embodiments described
herein, the one or more heat shields provided for the evaporation
source can include sheet metals surrounding the respective portions
of the evaporation sources, such as the distribution pipe 106
and/or the evaporation crucible 104. For example, the sheet metals
can have thicknesses of 0.1 mm to 3 mm, can be selected from at
least one material selected from the group consisting of ferrous
metals (SS) and non-ferrous metals (Cu, Ti, Al), and/or can be
spaced with respect to each other, for example by a gap of 0.1 mm
or more.
[0051] According to some embodiments, as exemplarily shown with
respect to FIGS. 2A to 2B, the evaporation crucible 104 is provided
at a lower side of the distribution pipe 106. According to yet
further embodiments, which can be combined with other embodiments
described herein, a vapor conduit 732 can be provided to the
distribution pipe 106 at the central portion of the distribution
pipe or at another position between the lower end of the
distribution pipe and the upper end of the distribution pipe. FIG.
2C illustrates an example of the evaporation source having a
distribution pipe 106 and a vapor conduit 732 provided at a central
portion of the distribution pipe. Vapor of organic material is
generated in the evaporation crucible 104 and is guided through the
vapor conduit 732 to the central portion of the distribution pipes
106. The vapor exits the distribution pipe 106 through a plurality
of openings or outlets 712. The distribution pipe 106 is supported
by a support 102 as described with respect to other embodiments
described herein. According to yet further embodiments, which can
be combined with other embodiments described herein, two or more
vapor conduits 732 can be provided at different positions along the
length of the distribution pipe 106. Thereby, the vapor conduits
732 can either be connected to one evaporation crucible 104 or to
several evaporation crucibles 104. For example, each vapor conduit
732 can have a corresponding evaporation crucible 104.
Alternatively, the evaporation crucible 104 can be in fluid
communication with two or more vapor conduits 732, which are
connected to the distribution pipe 106.
[0052] As described herein, the distribution pipe can be a hollow
cylinder. Thereby, the term cylinder can be understood as commonly
accepted as having a circular bottom shape and a circular upper
shape and a curved surface area or shell connecting the upper
circle and the little lower circle. Thereby, embodiments described
herein provide for a reduced heat transfer to the mask by heat
shields and cooling shield arrangements. For example, the heat
transfer from the evaporation source to the mask can be reduced by
having nozzles penetrating through the heat shields and the cooling
shield arrangements. According to further additional or alternative
embodiments, which can be combined with other embodiments described
herein, the term cylinder can further be understood in the
mathematical sense as having an arbitrary bottom shape and an
identical upper shape and a curved surface area or shell connecting
the upper shape and the lower shape. Accordingly, the cylinder does
not necessarily need to have a circular cross-section. Instead, the
base surface and the upper surface can have a shape different from
a circle. Specifically, the cross-section can have a shape as will
be described in more detail with respect to FIGS. 3A to 4 and 6A to
8B.
[0053] FIG. 3A shows a cross-section of a distribution pipe 106.
The distribution pipe 106 has walls 322, 326, and 324, which
surround an inner hollow space 710. The wall 322 is provided at an
outlet side of the evaporation crucible, at which the outlets 712
are provided. According to some embodiments, which can be combined
with other embodiments described herein, and outlet 712 can be
provided by the nozzle 312. The cross-section of the distribution
pipe can be described as being essentially triangular, that is the
main section of the distribution pipe corresponds to a portion of a
triangle and/or the cross-section of the distribution pipe can be
triangular with rounded corners and/or cut-off corners. As shown in
FIG. 3A, for example the corner of the triangle at the outlet side
is cut off.
[0054] The width of the outlet side of the distribution pipe, e.g.
the dimension of the wall 322 in the cross-section shown in FIG.
3A, is indicated by arrow 352. Further, the other dimensions of the
cross-section of the distribution pipe 106 are indicated by arrows
354 and 355. According to embodiments described herein, the width
of the outlet side of the distribution pipe is 30% or less of the
maximum dimension of the cross-section, e.g. 30% of the larger
dimension of the dimensions indicated by arrows 354 and 355. In
light thereof, outlet 712 of neighboring distribution pipes 106 can
be provided at a smaller distance. The smaller distance improves
mixing of organic materials, which are evaporated next to each
other. This can be better understood when referring to FIGS. 3C,
6A, 6B, and 7. Yet further, additionally or alternatively, and
independent of the improved mixing of organic materials, the width
of the wall facing the deposition area, or substrate respectively,
in an essentially parallel manner, can be reduced. Correspondingly,
the surface area of a wall facing a deposition area, or substrate
respectively, in an essentially parallel manner, e.g. wall 322, can
be reduced. This reduces the heat load provided to a mask or
substrate, which are supported in the deposition area or slightly
before the deposition area.
[0055] FIG. 3B illustrates further details of the distribution pipe
106 according to some embodiments described herein. One or more
heating elements 380 are provided at the walls surrounding the
inner hollow space 710. The heating devices can be electrical
heaters which are mounted to the walls of the distribution pipe.
For example, the heating devices can be provided by heating wires,
e.g. coated heating wires, which are clamped or otherwise fixed to
the distribution pipe 106.
[0056] Two or more heat shields 372 are provided around the one or
more heating elements 380. For example, the heat shields 372 can be
spaced apart from each other. Protrusions 373, which can be
provided as spots on one of the heat shields, separate the heat
shields with respect to each other. Accordingly, a stack of heat
shields 372 is provided. For example, two or more heat shields,
such as five or more heat shields or even 10 heat shields can be
provided. According to some embodiments, this stack is designed in
a way that compensates for the thermal expansion of the source
during the process, so that the nozzles are never blocked.
According to yet further embodiments, which can be combined with
other embodiments described herein, the outermost shield can be
water-cooled.
[0057] As exemplarily shown in FIG. 3B, the outlet 712, which is
shown in the cross-section shown in FIG. 3B, is provided with a
nozzle 312. The nozzle 312 extends through the heat shields 372.
This can reduce condensation of organic material at the heat
shields, as the nozzle guides the organic material through this
stack of heat shields. The nozzle can be heated to a temperature,
which is similar to the temperature inside the distribution pipe
106. In order to improve heating of the nozzle 312, a nozzle
support portion 412 can be provided, which is in contact with the
heated walls of the distribution pipe, as for example shown in FIG.
4.
[0058] FIG. 3C shows an embodiment, where two distribution pipes
are provided next to each other. Accordingly, an evaporation source
having a distribution pipe arrangement as shown in FIG. 3C can
evaporate two organic materials next to each other. Such an
evaporation source can thus also be referred to as an evaporation
source array. As shown in FIG. 3C, the shape of the cross-section
of the distribution pipes 106 allow to place the outlets or nozzles
of neighboring distribution pipes close to each other. According to
some embodiments, which can be combined with other embodiments
described herein, a first outlet or nozzle of the first
distribution pipe and a second outlet or nozzle of the second
distribution pipe can have a distance of 25 mm or below, such as
from 5 mm to 25 mm. More specifically, the distance of the first
outlet or nozzle to a second outlet or nozzle can be 10 mm or
below.
[0059] According to yet further embodiments, which can be combined
with other embodiments described herein, tube extensions of the
nozzles 312 can be provided. In light of the small distance between
the distribution pipes, such tube extensions can be sufficiently
small to avoid clogging or condensation therein. Tube extensions
can be designed such that nozzles of two or even three sources can
be provided in one line above each other, i.e. in one line along
the extension of the distribution pipe, which can be a vertical
extension. With this special design it is even possible to arrange
the nozzles of the two or three sources in one line over small tube
extensions, so that a perfect mixing is achieved.
[0060] FIG. 3C further illustrates the reduced heat load according
to embodiments described herein. A deposition area 312 is shown in
FIG. 3C. Typically a substrate can be provided in the deposition
area for deposition of organic material on a substrate. The angle
395 between the sidewall 326 and the deposition area 312 is
indicated in FIG. 3C. As can be seen, the sidewall 326 is inclined
by a comparably large angle such that the heat radiation, which
might occur in spite of the heat shields and cooling elements is
not directly radiated towards the deposition area. According to
some embodiments, which can be combined with other embodiments
described herein, the angle 395 can be 15.degree. or more.
Accordingly, the dimension or area, which is indicated by arrow
392, is significantly smaller as compared to the dimension or area,
which is indicated by arrow 394. Thereby, the dimension indicated
by arrow 392 corresponds to the dimension of the cross-section of
the distribution pipes 106, for which the surface facing the
deposition area is essentially parallel or has an angle of
30.degree. or less or even 15.degree. or less. The corresponding
area, i.e. the area which provides direct heat load to the
substrate, is the dimension shown in FIG. 3C multiplied with the
length of the distribution pipes. The dimension indicated by arrow
394 is a projection on the deposition area 312 of the entire
evaporation source in the respective cross-section. The
corresponding area, i.e. the area of the projection onto the
surface of the deposition area, is the dimension (arrow 394) shown
in FIG. 3C multiplied with the length of the distribution pipes.
According to embodiments described herein, which can be combined
with other embodiments described herein, the area indicated by
arrow 392 can be 30% or less as compared to the area indicated by
arrow 394. In light of the above, the shape of the distribution
pipes 106 reduces the direct heat load radiated towards the
deposition area. Accordingly, temperature stability of the
substrate and a mask provided in front of the substrate can be
improved.
[0061] FIG. 4 illustrates yet further optional modifications of
evaporation sources according to embodiments described herein. FIG.
4 shows a cross-section of a distribution pipe 106. Walls of the
distribution pipe 106 surround the inner hollow space 710. Vapor
can exit the hollow space through nozzle 312. In order to improve
heating of the nozzle 312, a nozzle support 412 is provided, which
is in contact with the heated walls of the distribution pipe 106.
The outer shield 402, which surrounds the distribution pipe 106 is
a cooled shield for further reducing the heat load. Further, a
cooled shield 404 is provided to additionally reduce the heat load
directed towards the deposition area or a substrate,
respectively.
[0062] According to some embodiments, which can be combined with
other embodiments described herein, the cooled shields can be
provided as metal plates having conduits for cooling fluid, such as
water, attached thereto or provided therein. Additionally, or
alternatively, thermoelectric cooling means or other cooling means
can be provided to cool the cooled shields. Typically, the outer
shields, i.e. the outermost shields surrounding the inner hollow
space of a distribution pipe, can be cooled.
[0063] FIG. 4 illustrates a further aspect, which can be provided
according to some embodiments. Shaper shields 405 are shown in FIG.
4. The shaper shields typically extend from a portion of the
evaporation source towards the substrate or the deposition area.
Accordingly, the direction of the vapor existing the distribution
pipe or pipes through the outlets can be controlled, i.e. the angle
of the vapor emission can be reduced. According to some
embodiments, at least a portion of the organic material evaporated
through the outlets or nozzles is blocked by the shaper shield.
Thereby, the width of the emission angle can be controlled.
According to some implementations, the shaper shields 405 can be
cooled similar to the cooled shields 402 and 402 in order to
further reduce the heat radiation emitted towards the deposition
area.
[0064] FIG. 5A shows a portion of an evaporation source. According
to some embodiments, which can be combined with other embodiments
described herein, the evaporation source or the evaporation source
array is a vertical linear source. Accordingly, the three outlets
712 are a portion of a vertical outlet array. FIG. 5A illustrates a
stack of heat shields 572, which can be attached to the
distribution pipe by fixation element 573, e.g. a 3screw or the
like. Further, the outer shield 404 is a cooled shield having
further openings provided therein. According to some embodiments,
which can be combined with other embodiments described herein, the
design of the outer shield can be configured to allow for thermal
extension of the components of the evaporation source, wherein the
openings maintain alignment with the nozzles of the distribution
pipe or reach alignment with the nozzles of the distribution pipe
when the operation temperature is reached. FIG. 5B shows a side
view of a cooled outer shield 404. The cooled outer shield can
essentially extend along the length of the distribution pipe.
Alternatively, two or three cooled outer shields can be provided
next to each other to extend along the length of the distribution
pipe. The cooled outer shield is attached to the evaporation source
by fixation element 502, e.g. a screw, wherein the fixation element
is provided essentially in the center (.+-.10% or .+-.20%) of the
distribution pipe along the length extension. Upon thermal
expansion of the distribution pipe the length of the portion of the
outer shield 404, which is subject to thermal extension is reduced.
The openings 531 in the outer shield 404 can be circular close to
the fixation element 532 and can have an oval shape at a larger
distance to the fixation element. According to some embodiments,
the length of the openings 531 in a direction parallel to the
longitudinal axis of the evaporation pipe can be increased the
larger the distance from the fixation element is. Typically, the
width of the openings 531 in a direction perpendicular to the
longitudinal axis of the evaporation pipe can be constant. In light
of the above, the outer shield 404 can extend upon thermal
expansion particularly along the longitudinal axis of the
evaporation pipe and the increased dimension parallel to the
longitudinal axis of the evaporation pipe can compensate or at
least partially for the thermal expansion. Accordingly, the
evaporation source can be operated in a wide temperature range
without the openings in the outer shield 404 blocking the
nozzles.
[0065] FIG. 5C illustrates a further optional feature of
embodiments described herein, which can likewise also be provided
for other embodiments described herein. FIG. 5C shows a side view
from the side of wall 322 (see FIG. 3A), wherein a shield 572 is
provided at the wall 322. Further, the side wall 326 is shown in
FIG. 5C. As can be seen in FIG. 5C the shield 572 or the shields in
the stack of shields are segmented along the length of the
evaporation pipe. Thereby, the length of shield portion can be 200
mm or below, e.g. 120 mm or below, such as 60 mm to 100 mm.
Accordingly, the length of the shield portions, e.g. the stack of
shields is reduced in order to reduce thermal expansion thereof.
Accordingly, the alignment of the openings in the shield, through
which the nozzles can extend and which correspond to the outlets
712, is less critical.
[0066] According to yet further embodiments, which can be combined
with other embodiments described herein, two or more heat shields
372 are provided around the inner hollow space 710 and the heated
portion of the distribution pipe 106. Accordingly, the heat
radiation towards the substrate, the mask or another portion of a
deposition apparatus from the heated portion of the distribution
pipe 106 can be reduced. According to one example, as shown in FIG.
5, more layers of heat shields 572 can be provided at the side at
which the openings or outlets are provided. A stack of heat shields
is provided. According to typical embodiments, which can be
combined with other embodiments described herein, the heat shields
372 and/or 572 are spaced apart from each other, for example by 0.1
mm to 3 mm. According to some embodiments, which can be combined
with other embodiments described herein, the stack of heat shields
is designed as described with respect to FIGS. 5A to 5C such that
compensates for the thermal expansion of the source during the
process, so that the nozzles are never blocked. Additionally the
outermost shield can be cooled, e.g. water cooled. Thus, according
to some embodiments, an outer shield 404, particularly at the side
at which the openings are provided, can be a cooled shield, e.g.
having cone shaped openings provided therein. Accordingly, such an
arrangement allows for a temperature stability with a deviation of
.DELTA.T of 1.degree. C. even if the nozzles have a temperature of
about 400.degree. C.
[0067] FIG. 6 shows a further view of an evaporation source 100. An
evaporation crucible 104 is provided for evaporating the organic
material. A heating element (not shown in FIG. 6) is provided for
heating the evaporation crucible 104. The distribution pipe 106 is
in fluid communication with the evaporation crucible, such that
organic material evaporated in the evaporation crucible can be
distributed in the distribution pipe 106. The evaporated organic
material exits the distribution pipe 106 through openings (not
shown in FIG. 6.) The evaporation crucible 106 has sidewalls 326, a
wall 324 opposing the wall at the outlet side and a top wall 325.
The walls are heated by heating element 380, which are mounted or
attached to the walls. According to some embodiments, which can be
combined with other embodiments described herein, the evaporation
source and/or one or more of the walls respectively, can be made of
quartz or titanium. Specifically, the evaporation source and/or one
or more of the walls can be made of titanium. Both sections, the
evaporation crucible 104 and the distribution pipe 106, can be
heated independently from each other.
[0068] Shield 404, which further reduces the heat radiation towards
the deposition area, is cooled by cooling element 680. For example,
conduits for having a cooling fluid provided therein can be mounted
to the shield 404. As shown in FIG. 6, additionally shaper shields
405 can be provided at the cooling shield 404. According to some
embodiments, which can be combined with other embodiments described
herein, the shaper shield can also be cooled, e.g. water cooled.
For example, the shaper shield can be attached to the cooling
shield or cooling shield arrangement. The thickness uniformity of
the deposited film of organic material can be tuned over the nozzle
array and additional shaper shields, which can be placed aside of
the one or more outlets or nozzles. The compact design of the
source allows for moving the source with a driving mechanism in a
vacuum chamber of a deposition apparatus. In this case all
controllers, power supplies and additional support functions are
implemented in an atmospheric box, which is attached to the
source.
[0069] FIGS. 7A and /B show further top views including a
cross-section of distribution pipes 106. FIG. 7A shows an
embodiment having three distribution pipes 706, which are provided
over an evaporator control housing 702. The evaporator control
housing is configured to maintain atmospheric pressure therein and
is configured to house at least one element selected from the group
consisting of: a switch, a valve, a controller, a cooling unit, a
cooling control unit, a heating control unit, a power supply, and a
measurement device. Accordingly, a component for operating the
evaporation source for the evaporation source array can be provided
under atmospheric pressure close to the evaporation crucible and
the distribution pipe and can be moved through the deposition
apparatus together with the evaporation source.
[0070] The distribution pipes 106 shown in FIG. 7A are heated by
heating element 380. A cooled shield 402 is provided surrounding
the distribution pipes 106. According to some embodiments, which
can be combined with other embodiments described herein, one cooled
shield can surround two or more distribution pipes 106. The organic
materials, which are evaporated in an evaporation crucible are
distributed in a respective one of the distribution pipes 106 and
can exit the distribution pipe through outlets 712. Typically, a
plurality of outlets are distributed along the length of the
distribution pipe 106. FIG. 7B shows an embodiment similar to FIG.
7A, wherein two distribution pipes are provided. The outlets are
provided by nozzles 312. Each distribution pipe is in fluid
communication with the evaporation crucible (not shown in FIGS. 7A
and 7B), and wherein the distribution shape has a cross-section
perpendicular to the length of the distribution pipe, which is
non-circular, and which includes an outlet side at which the one or
more outlets are provided, wherein the width of the outlet side of
the cross-section is 30% or less of the maximum dimension of the
cross-section.
[0071] FIG. 8A illustrates yet further embodiments described
herein. Three distribution pipes 106 are provided. An evaporator
control housing 702 is provided adjacent to the distribution pipes
and connected thereto via a thermal insulator 879. As described
above, the evaporator control housing, configured to maintain
atmospheric pressure therein, is configured to house at least one
element selected from the group consisting of: a switch, a valve, a
controller, a cooling unit, a cooling control unit, a heating
control unit, a power supply, and a measurement device. In addition
to the cooled shield 402, the cooled shield 404 is provided, which
has sidewalls 804. The cooled shield 404 and the sidewalls 804
provide a U-shaped cooled heat shield to reduce the heat radiation
towards the deposition area, i.e. a substrate and/or a mask. Arrows
811, 812, and 813, respectively illustrate evaporated organic
material exiting distribution pipes 106. Due to the essentially
triangular shape of the distribution pipes, the evaporation cones
originating from the three distribution pipes are in close
proximity to each other, such that mixing of the organic materials
from the different distribution pipes can be improved.
[0072] As further shown in FIG. 8A, shaper shields 405 are
provided, for example, attached to the cooled shield 404 or as a
part of the cooled shield 404. According to some embodiments, the
shaper shields 405 can also be cooled to further reduce the heat
load emitted towards the deposition area. The shaper shields
delimit the distribution cone of the organic materials distributed
towards the substrates, i.e. the shaper shields are configured to
block at least a portion of the organic materials.
[0073] FIG. 8B shows a cross-sectional view of yet another
evaporation source according to embodiments described herein. Three
distribution pipes are shown, wherein each distribution pipes are
heated by heating elements (not shown in FIG. 8A). The vapor
generated in evaporation crucibles (not shown) exit the
distribution pipe through nozzles 312 and 512 respectively. In
order to have the outlets 712 of the nozzles closer together, the
outer nozzles 512 include tube extensions, which include short
tubes extending towards the nozzle tubes of the center distribution
pipe. Thereby, according to some embodiments, the tube extensions
512 can have a bend such as a 60.degree. to 120.degree. bend, e.g.
a 90.degree. bend. A plurality of shields 572 are provided at the
outlet sidewall of the evaporation source. For example, at least 5
or even at least 7 shields 572 are provided at the outlet side of
the evaporation tube. A shield 402 is provided the one or more
distribution pipe, wherein cooling elements 822 are provided.
Between the distribution pipe and the shield 402 a plurality of
shields 372 are provided. For example, at least 2 or even at least
5 shields 372 are provided between the distribution pipe and the
shield 402. The plurality of shields 572 and the plurality of
shields 372 are provided as stacks of shields, e.g. wherein the
shields are distant from each other by 0.1 mm to 3 mm.
[0074] According to yet further embodiments, which can be combined
with other embodiments described herein, a further shield 812 can
be provided between the distribution pipes. For example, the
further shield 812 can be a cooled shield or a cooled lug. Thereby,
the temperature of the distribution pipes can be controlled
independent from each other. For example, in the event different
materials are evaporated through neighboring distribution pipes
(such as a host and a dopant), these materials may need to be
evaporated at different temperatures. Accordingly, the further
shield 812, e.g. a cooled shield, can reduce cross-talk between the
distribution pipes in an evaporation source or an evaporation
source array.
[0075] The embodiments described herein mostly relate to
evaporation sources and evaporation apparatuses for depositing
organic material on a substrate, while the substrate is essentially
vertically oriented. The essentially vertical substrate orientation
allows for a small footprint of deposition apparatuses and
specifically deposition systems including several deposition
apparatuses for coating several layers of organic material on a
substrate. Thereby, it can be considered that apparatuses described
herein are configured for large area substrate processing or
processing of a plurality of substrates in large area carriers. The
vertical orientation further allows for a good scalability for
current and future substrate size generations, that is present and
future glass sizes. Yet, the evaporation sources with the improved
cross sectional shape and the concept of heat shields and cooling
elements can also be provided for material deposition on horizontal
substrates.
[0076] FIGS. 9A and 9B show a yet further embodiment of deposition
apparatus 500. FIG. 9A shows a schematic top view of the deposition
apparatus 500. FIG. 9B shows a schematic cross-sectional side view
of the deposition apparatus 500. The deposition apparatus 500
includes a vacuum chamber 110. The valve 205, for example a gate
valve, allows for a vacuum seal to an adjacent vacuum chamber. The
valve can be open for transport of a substrate 121 or a mask 132
into the vacuum chamber 110 or out of the vacuum chamber 110. Two
or more evaporation sources 100 are provided in the vacuum chamber
110. The example shown in FIG. 9A shows seven evaporation sources.
According to typical embodiments, which can be combined with other
embodiments described herein, to evaporation sources, three
evaporation sources, or four evaporation sources can beneficially
be provided. As compared to a higher number of evaporation sources,
which may also be provided according to some embodiments, the
logistics of maintenance of the limited number of evaporation
sources (e.g. 2 to 4) might be easier. Accordingly, the cost of
ownership might be better for such systems.
[0077] According to some embodiments, which can be combined with
other embodiments described herein, and as for example shown in
FIG. 9A, the looped track 530 can be provided. The looped track 530
can include straight portions 534 and curved portions 533. The
looped track 530 provides for a translational movement of the
evaporation sources and the rotation of the evaporation sources. As
described above, the evaporation sources can typically be line
sources, e.g. linear vapor distribution showerheads.
[0078] According to some embodiments, which can be combined with
other embodiments described herein, the looped track includes a
rail or a rail arrangement, a roller arrangement or a magnetic
guide to move the one or more evaporation sources along the looped
track.
[0079] Based upon the looped track 530, a train of sources can move
with translational movement along a substrate 121, which is
typically masked by a mask 132. The curved portion 533 of the
looped track 530 provides a rotation of the evaporation source 100.
Further, the curved portion 533 can provide for positioning the
evaporation source in front of a second substrate 121. The further
straight portion 534 of the looped track 530 provides a further
translational movement along the further substrate 121. Thereby, as
mentioned above, according to some embodiments, which can be
combined with other embodiments described herein, the substrates
121 and the masks 132 remain essentially stationary during
deposition. The evaporation sources providing line sources, e.g.
line sources with an essentially vertical orientation of the line,
are moved along the stationary substrates.
[0080] According to some embodiments, which can be combined with
other embodiments described herein, a substrate 121 shown in vacuum
chamber 110 can be supported by a substrate support having rollers
403 and 424 and further, in a stationary deposition position, by a
substrate support 126, which are connected to alignment units 112.
An alignment unit 112 can adjust the position of the substrate 121
with respect to the mask 132. Accordingly, the substrate can be
moved relative to the mask 132 in order to provide for a proper
alignment between the substrate and the mask during deposition of
the organic material. According to a further embodiment, which can
be combined with other embodiments described herein, alternatively
or additionally the mask 132 and/or the mask frame 131 holding the
mask 132 can be connected to the alignment unit 112. Thereby,
either the mask can be positioned relative to the substrate 121 or
the mask 132 and the substrate 121 can both be positioned relative
to each other.
[0081] The embodiment shown in FIGS. 9A and 9B shows two substrates
121 provided in the vacuum chamber 110. Yet, particularly for
embodiments including a train of evaporation sources 100 in a
vacuum chamber at least three substrates or at least four
substrates can be provided. Thereby, sufficient time for exchange
of the substrate, i.e. transport of a new substrate into the vacuum
chamber and of a processed substrate out of the vacuum chamber, can
be provided even for a deposition apparatus 500 having a larger
number of evaporation sources and, thus, a higher throughput.
[0082] FIGS. 9A and 9B show the first transportation track for a
first substrate 121 and a second transportation track for a second
substrate 121. A first roller assembly is shown on one side of the
vacuum chamber 110. The first roller assembly includes rollers 424.
Further, the transportation system includes a magnetic guiding
element 524. Similarly, a second transportation system having
rollers and a magnetic guiding element is provided on the opposing
side of the vacuum chamber. The upper portions of the carriers 421
are guided by magnetic guiding elements 524. Similarly, according
to some embodiments, the mask frames 131 can be supported by
rollers 403 and magnetic guiding elements 503.
[0083] FIG. 9B exemplarily shows two supports 102 provided on a
respective straight portion 534 of the looped track 530.
Evaporation crucibles 104 and distribution pipes 106 are supported
by the respective supports 102. Thereby, FIG. 5B illustrates two
distribution pipes 106 supported by a support 102. The supports 102
are shown as being guided on the straight portions 534 of the
looped track. According to some embodiments, which can be combined
with other embodiments described herein, an actuator, a drive, a
motor, a drive belt, and/or a drive chain can be provided to move
the support 102 to along the looped track, i.e. along the straight
portions 534 of the looped track and along the curved portion 533
(see FIG. 9A) of the looped track.
[0084] According to embodiments of deposition apparatuses described
herein, a combination of the translational movement of a line
source, e.g. a linear vapor distribution showerhead, and the
rotation of the line source, e.g. a linear vapor distribution
showerhead, allows for a high evaporation source efficiency and a
high material utilization for OLED display manufacturing, wherein a
high precision of masking of the substrate is desired. A
translational movement of the source allows for a high masking
precision since the substrate and the mask can maintain stationary.
The rotational movement allows for a substrate exchange of one
substrate while another substrate is coated with organic material.
This significantly improves the material utilization as the idle
time, i.e. the time during which the evaporation source evaporates
organic material without coating a substrate, is significantly
reduced.
[0085] Embodiments described herein particularly relate to
deposition of organic materials, e.g. for OLED display
manufacturing and on large area substrates. According to some
embodiments, large area substrates or carriers supporting one or
more substrates, i.e. large area carriers, may have a size of at
least 0.174 m.sup.2. Typically, the size of the carrier can be
about 1.4 m.sup.2 to about 8 m.sup.2, more typically about 2
m.sup.2 to about 9 m.sup.2 or even up to 12 m.sup.2. Typically, the
rectangular area, in which the substrates are supported, for which
the holding arrangements, apparatuses, and methods according to
embodiments described herein are provided, are carriers having
sizes for large area substrates as described herein. For instance,
a large area carrier, which would correspond to an area of a single
large area substrate, can be GEN 5, which corresponds to about 1.4
m.sup.2 substrates (1.1 m.times.1.3 m), GEN 7.5, which corresponds
to about 4.29 m.sup.2 substrates (1.95 m.times.2.2 m), GEN 8.5,
which corresponds to about 5.7 m.sup.2 substrates (2.2 m.times.2.5
m), or even GEN 10, which corresponds to about 8.7 m.sup.2
substrates (2.85 m.times.3.05 m). Even larger generations such as
GEN 11 and GEN 12 and corresponding substrate areas can similarly
be implemented. According to typical embodiments, which can be
combined with other embodiments described herein, the substrate
thickness can be from 0.1 to 1.8 mm and the holding arrangement,
and particularly the holding devices, can be adapted for such
substrate thicknesses. However, particularly the substrate
thickness can be about 0.9 mm or below, such as 0.5 mm or 0.3 mm,
and the holding arrangement, and particularly the holding devices,
are adapted for such substrate thicknesses. Typically, the
substrate may be made from any material suitable for material
deposition. For instance, the substrate may be made from a material
selected from the group consisting of glass (for instance soda-lime
glass, borosilicate glass etc.), metal, polymer, ceramic, compound
materials, carbon fiber materials or any other material or
combination of materials which can be coated by a deposition
process.
[0086] In order to achieve good reliability and yield rates,
embodiments described herein keep the mask and substrate stationary
during the deposition of organic material. A movable linear source
for uniform coating of a large area substrate is provided. The idle
time is reduced as compared to an operation wherein after each
deposition the substrate needs to be exchanged including a new
alignment step of the mask and the substrate relative to each
other. During the idle time, the source is wasting material.
Accordingly, having a second substrate in a deposition position and
readily aligned with respect to the mask reduces the idle time and
increases the material utilization.
[0087] The embodiments described herein further provide evaporation
sources (or evaporation source arrays) having a reduced heat
radiation towards the deposition area, i.e. substrate and/or a mask
such that the mask can be held at an essentially constant
temperature which is within the temperature range of 5.degree. C.
or below or even within a temperature range of 1.degree. C. or
below. Yet further, the shape of the distribution pipe or
distribution pipes with the small width at the outlet side reduces
the heat load on the mask and further improves mixing of different
organic materials because the outlets of neighboring distribution
pipes can be provided in close proximity, e.g. at a distance of 25
mm or below.
[0088] According to typical embodiments, which can be combined with
other embodiments described herein, an evaporation source includes
at least one evaporation crucible, and at least one distribution
pipe, e.g. at least one linear vapor distribution showerhead.
However, an evaporation source can include two or three, eventually
even four or five evaporation crucibles and corresponding
distribution pipes. Thereby, different organic materials can be
evaporated in at least two of the several crucibles, such that the
different organic materials form one organic layer on the
substrate. Additionally or alternatively, similar organic materials
can be evaporated in at least two of the several crucibles, such
that the deposition rate can be increased. This is particularly
true as organic materials can often only be evaporated in a
relatively small temperature range (e.g. 20.degree. C. or even
below) and the evaporation rate can, thus, not be greatly increased
by increasing the temperature in the crucible.
[0089] According to embodiments described herein, the evaporation
sources, the deposition apparatuses, the methods of operating
evaporation sources and/or deposition apparatuses, and the methods
of manufacturing evaporation sources and/or deposition apparatuses
are configured for a vertical deposition, i.e. the substrate is
supported in an essentially vertical orientation (e.g.
vertical+-10.degree.), during layer deposition. Further, a
combination of a line source, a translational movement and a
rotation of the evaporation direction, particularly a rotation
around an axis being essentially vertical, e.g. parallel to the
substrate orientation and/or the direction of the line-extension of
the line source, allows for a high material utilization of about
80% or above. This is an improvement of at least 30% as compared to
other systems.
[0090] A movable and turnable evaporation source within the process
chamber, i.e. the vacuum chamber for layer deposition therein,
allows for a continuous or almost continuous coating with high
material utilization. Generally, embodiments described herein allow
for a high evaporation source efficiency (>85%) and a high
material utilization (at least 50% or above) by using a scanning
source approach with 180.degree. turning mechanism to coat two
substrates alternating. Thereby, the source efficiency takes into
consideration material losses occurring due to the fact that the
vapor beams extend over the size of the large area substrates in
order to allow for a uniform coating of the entire area of the
substrate which is to be coated. The material utilization
additionally considers losses occurring during idle times of the
evaporation source, i.e. times where the evaporation source cannot
deposit the evaporated material on a substrate.
[0091] Yet further, the embodiments described herein and relating
to a vertical substrate orientation allow for a small footprint of
deposition apparatuses and specifically deposition systems
including several deposition apparatuses for coating several layers
of organic material on a substrate. Thereby, it can be considered
that apparatuses described herein are configured for large area
substrate processing or processing of a plurality of substrates in
large area carriers. The vertical orientation further allows for a
good scalability for current and future substrate size generations,
that is present and future glass sizes.
[0092] FIG. 10 shows a system 1000 for manufacturing devices,
particularly devices including organic materials therein. For
example, the devices can be electronic devices or semiconductor
devices, such as optoelectronic devices and particularly displays.
Evaporation sources as described herein can beneficially be
utilized in a system as described with respect to FIG. 10. An
improved carrier handling and/or mask handling of a mass production
system can be provided by a system 1000. According to typical
embodiments, which can be combined with other embodiments described
herein, these improvements can be beneficially utilized for OLED
device manufacturing and can, thus, include evaporation sources,
deposition apparatuses, components thereof, as described with
respect to FIGS. 1 to 9B. Embodiments described herein particularly
relate to deposition of materials, e.g. for display manufacturing
and on large area substrates. According to some embodiments, large
area substrates or carriers supporting one or more substrates, i.e.
large area carriers, may have a size of at least 0.174 m.sup.2.
Typically, the size of the carrier can be about 1.4 m.sup.2 to
about 8 m.sup.2, more typically about 2 m.sup.2 to about 9 m.sup.2
or even up to 12 m.sup.2. Typically, the rectangular area, in which
the substrates are supported and for which the holding
arrangements, apparatuses, and methods according to embodiments
described herein are provided, are carriers having sizes for large
area substrates as described herein. For instance, a large area
carrier, which would correspond to an area of a single large area
substrate, can be GEN 5, which corresponds to about 1.4 m.sup.2
substrates (1.1 m.times.1.3 m), GEN 7.5, which corresponds to about
4.29 m.sup.2 substrates (1.95 m.times.2.2 m), GEN 8.5, which
corresponds to about 5.7 m.sup.2 substrates (2.2 m.times.2.5 m), or
even GEN 10, which corresponds to about 8.7 m.sup.2 substrates
(2.85 m.times.3.05 m). Even larger generations such as GEN 11 and
GEN 12 and corresponding substrate areas can similarly be
implemented. According to typical embodiments, which can be
combined with other embodiments described herein, the substrate
thickness can be from 0.1 to 1.8 mm and the holding arrangement,
and particularly the holding devices, can be adapted for such
substrate thicknesses. However, particularly the substrate
thickness can be about 0.9 mm or below, such as 0.5 mm or 0.3 mm,
and the holding arrangement, and particularly the holding devices,
are adapted for such substrate thicknesses. Typically, the
substrate may be made from any material suitable for material
deposition. For instance, the substrate may be made from a material
selected from the group consisting of glass (for instance soda-lime
glass, borosilicate glass etc.), metal, polymer, ceramic, compound
materials, carbon fiber materials or any other material or
combination of materials which can be coated by a deposition
process.
[0093] The coater or deposition system concepts, e.g. for OLED mass
production according to some embodiments, provides a vertical
cluster approach, such that for example "random" access to all
chamber may be provided. Accordingly, such concepts are efficient
for both RGB and White on CF (color filter) deposition by offering
flexibility in adding a desired number of modules required. This
flexibility could also be used to create redundancy. Generally, for
OLED display manufacturing two concepts can be provided. On the one
hand, RGB (red green blue) displays having emission of red light,
green light, and blue light are manufactured. On the other hand,
White on CF displays are manufactured, wherein white light is
emitted and colors are generated by a color filter. Even though
White on CF displays requires a reduced number of chambers for
manufacturing such a device, both concepts are in practice and have
their pros and cons.
[0094] According to embodiments described herein, which can be
combined with other embodiments described herein, OLED device
manufacturing typically includes masking of the substrates for
deposition. Further, the large area substrates are typically
supported by a carrier during processing thereof. Both mask
handling and carrier handling can be critical particularly for OLED
devices with respect to temperature stability, cleanliness of mask
and carrier and the like. Accordingly, embodiments described herein
provide a carrier return path under vacuum conditions or under a
defined gas atmosphere, e.g. a protective gas, and improved
cleaning options for carriers and masks.
[0095] According to yet further embodiments, which can be combined
with other embodiments described herein, mask cleaning can be
provided either in-situ, for example by an optional plasma cleaning
or can be provided by offering a mask exchange interface to allow
for external mask cleaning without venting processing chambers or
transfer chambers of the manufacturing system.
[0096] The manufacturing system 1000 shown in FIG. 10 includes a
load lock chamber 1120, which is connected to a horizontal
substrate handling chamber 1100. The substrate can be transferred
from the glass handling chamber 1102 to a vacuum swing module 1160,
wherein the substrate is loaded in a horizontal position on a
carrier. After loading the substrate on the carrier in the
horizontal position, the vacuum swing module 1160 rotates the
carrier having the substrate provided thereon in a vertical or
essentially vertical orientation. The carrier having the substrate
provided thereon is then transferred through a first transfer
chamber 610 and at least one further transfer chamber (611-615)
having the vertical orientation. One or more deposition apparatuses
200 can be connected to the transfer chambers. Further, other
substrate processing chambers or other vacuum chambers can be
connected to one or more of the transfer chambers. After processing
of the substrate, the carrier having a substrate thereon is
transferred from the transfer chamber 615 into a further vacuum
swing module 1161 in the vertical orientation. The further vacuum
swing module 1161 rotates the carrier having a substrate thereon
from the vertical orientation to a horizontal orientation.
Thereafter, the substrate can be unloaded into a further horizontal
glass handling chamber 1101. The processed substrate may be
unloaded from the processing system 1000 through load lock chamber
1121, for example after the manufactured device is encapsulated in
one of the thin-film encapsulation chambers 1140 or 1141.
[0097] In FIG. 10, a first transfer chamber 610, a second transfer
chamber 611, a third transfer chamber 612, a fourth transfer
chamber 613, a fifth transfer chamber 614, and a sixth transfer
chamber 615 are provided. According to embodiments described
herein, at least two transfer chambers are included in a
manufacturing system, typically 2 to 8 transfer chambers can be
included in the manufacturing system. Several deposition
apparatuses, for example 9 deposition apparatuses 200 in FIG. 11,
each having a vacuum chamber 110 and each being exemplarily
connected to one of the transfer chambers are provided. According
to some embodiments, one or more of the vacuum chambers of the
deposition apparatuses are connected to the transfer chambers via
gate valves 205.
[0098] Alignment units 112 can be provided at the vacuum chambers
110. According to yet further embodiments, which can be combined
with other embodiments described herein, vacuum maintenance
chambers 210 can be connected to the vacuum chambers 110, for
example via gate valve 207. The vacuum maintenance chambers 210
allow for maintenance of deposition sources in the manufacturing
system 1000.
[0099] According to some embodiments, and as shown in FIG. 10, the
one or more transfer chambers 610-615 are provided along a line for
providing an in-line transportation system portion. According to
some embodiments described herein, which can be combined with other
embodiments described herein, a dual track transportation
arrangement is provided wherein the transfer chambers include a
first track 1111 and a second track 1112 in order to transfer
carriers, i.e. carriers supporting substrates, along at least one
of the first track and the second track. The first tracks 1111 and
the second tracks 1112 in the transfer chambers provide a dual
track transportation arrangement in the manufacturing system
1000.
[0100] According to yet further embodiments, which can be combined
with other embodiments described herein, one or more of the
transfer chambers 610-615 are provided as a vacuum rotation module.
The first track 1111 and the second track 1112 can be rotated by at
least 90.degree., for example by 90.degree., 180.degree. or
360.degree.. The carriers on the tracks are rotated in the position
to be transferred in one of the vacuum chambers of the deposition
apparatuses 200 or one of the other vacuum chambers described
below. The transfer chambers are configured to rotate the
vertically oriented carriers and/or substrates, wherein for example
that tracks in the transfer chambers are rotated around a vertical
rotation axis. This is indicated by the arrows in FIG. 10.
[0101] According to some embodiments, which can be combined with
other embodiments described herein, the transfer chambers are
vacuum rotation modules for a rotation substrate under a pressure
below 10 mbar. According to yet further embodiments, which can be
combined with other embodiments described herein, a further track
is provided within the two or more transfer chambers (610-615),
wherein a carrier return track is provided. According to typical
embodiments, the carrier return track 1125 can be provided between
the first track 1111 and second track 1112. The carrier return
track 1125 allows for returning empty carriers from the further
vacuum swing module 1161 to the vacuum swing module 1160 under
vacuum conditions. Returning the carriers under vacuum conditions
and optionally under controlled inert atmosphere (e.g. Ar, N.sub.2
or combinations thereof) reduces the carriers' exposure to ambient
air. Contact to moisture can be reduced or avoided. Thus, the
outgassing of the carriers during manufacturing of the devices in
the manufacturing system 1000 can be reduced. This may improve the
quality of the manufactured devices and/or the carriers can be in
operation without being cleaned for an extended time.
[0102] FIG. 10 further shows a first pretreatment chamber 1130 and
a second pretreatment chamber 1131. A robot (not shown) or another
handling system can be provided in the substrate handling chamber
1100. The robot or the another handling system can load the
substrate from the load lock chamber 1120 in the substrate handling
chamber 1100 and transfer the substrate into one or more of the
pretreatment chambers (1130, 1131). For example, the pretreatment
chambers can include a pretreatment tool selected from the group
consisting of: plasma pretreatment of the substrate, cleaning of
the substrate, UV and/or ozone treatment of the substrate, ion
source treatment of the substrate, RF or microwave plasma treatment
of the substrate, and combinations thereof. After pretreatment of
the substrates, the robot or another handling system transfers the
substrate out of the pretreatment chamber via the substrate
handling chamber into the vacuum swing module 1160. In order to
allow for venting the load lock chamber 1120 for loading of the
substrates and/or for handling of the substrate in the substrate
handling chamber 1100 under atmospheric conditions, a gate valve
205 is provided between the substrate handling chamber 1100 and the
vacuum swing module 1160. Accordingly, the substrate handling
chamber 1100, and if desired one or more of the load lock chamber
1120, the first pretreatment chamber 1130 and the second
pretreatment chamber 1131, can be evacuated before the gate valve
205 is opened and the substrate is transferred into the vacuum
swing module 1160. Accordingly, loading, treatment and processing
of substrates may be conducted under atmospheric conditions before
the substrate is loaded into the vacuum swing module 1160.
[0103] According to embodiments described herein, which can be
combined with other embodiments described herein, loading,
treatment and processing of substrates, which may be conducted
before the substrate is loaded into the vacuum swing module 1160 is
conducted while the substrate is horizontally oriented or
essentially horizontally oriented. The manufacturing system 1000 as
shown in FIG. 10, and according to yet further embodiments
described herein, combines a substrate handling in a horizontal
orientation, a rotation of the substrate in a vertical orientation,
material deposition onto the substrate in the vertical orientation,
a rotation of the substrate in a horizontal orientation after the
material deposition, and an unloading of the substrate in a
horizontal orientation.
[0104] The manufacturing system 1000 shown in FIG. 10, as well as
other manufacturing systems described herein, includes at least one
thin-film encapsulation chamber. FIG. 11 shows a first thin-film
encapsulation chamber 1140 and a second thin-film encapsulation
chamber 1141. The one or more thin-film encapsulation chambers
include an encapsulation apparatus, wherein the deposited and/or
processed layers, particularly an OLED material, are encapsulated
between, i.e. sandwiched between, the processed substrate and a
further substrate in order to protect the deposited and/or
processed material from being exposed to ambient air and/or
atmospheric conditions. Typically, the thin-film encapsulation can
be provided by sandwiching the material between two substrates, for
example glass substrates. However, other encapsulation methods like
lamination with glass, polymer or metal sheets, or laser fusing of
a cover glass may alternatively be applied by an encapsulation
apparatus provided in one of the thin-film encapsulation chambers.
In particular, OLED material layers may suffer from exposure to
ambient air and/or oxygen and moisture. Accordingly, the
manufacturing system 1000, for example as shown in FIG. 10, can
encapsulate the thin films before unloading the processed substrate
via load lock chamber 1121.
[0105] The manufacturing system 1000 shown in FIG. 10, as well as
other manufacturing systems described herein, can further include a
layer inspection chamber 1150. A layer inspection tool, such as an
electron and/or ion layer inspection tool, can be provided in the
layer inspection chamber 1150. Layer inspection can be conducted
after one or more depositions steps or processing steps provided in
the manufacturing system 1000. Therefore, a carrier having a
substrate therein can be moved from a deposition or processing
chamber to the transfer chamber 611 to which the layer inspection
chamber 1150 is connected via gate valve 205. The substrate to be
inspected can be transferred in the layer inspection chamber and
inspected within the manufacturing system, i.e. without removing
the substrate from the manufacturing system. An online layer
inspection can be provided after one or more of the deposition
steps or processing steps, which may be conducted in the
manufacturing system 1000.
[0106] According to yet further embodiments, which can be combined
with other embodiments described herein, the manufacturing system
can include a carrier buffer 1421. For example, the carrier buffer
can be connected to the first transfer chamber 610, which is
connected to the vacuum swing module 1160 and/or the last transfer
chamber, i.e. the sixth transfer chamber 615. For example, the
carrier buffer can be connected to one of the transfer chambers,
which is connected to one of the vacuum swing modules. Since the
substrates are loaded and unloaded in the vacuum swing modules, it
is beneficial if the carrier buffer 1421 is provided close to a
vacuum swing module. The carrier buffer is configured to provide
the storage for one or more, for example 5 to 30, carriers. The
carriers in the buffer can be used during operation of the
manufacturing system in the event another carrier needs to be
replaced, for example for maintenance, such as cleaning.
[0107] According to yet further embodiments, which can be combined
with other embodiments described herein, the manufacturing system
can further include a mask shelf 1132, i.e. a mask buffer. The mask
shelf 1132 is configured to provide storage for replacement masks
and or masks, which need to be stored for specific deposition
steps. According to methods of operating a manufacturing system
1000, a mask can be transferred from the mask shelf 1132 to a
deposition apparatus 200 via the dual track transportation
arrangement having the first track 1111 and the second track 1112.
Thus, a mask in a deposition apparatus can be exchanged either for
maintenance, such as cleaning, or for a variation of a deposition
pattern without venting a deposition apparatus, without venting a
transfer chamber, and/or without exposing the mask to atmospheric
pressure.
[0108] FIG. 10 further shows a mask cleaning chamber 1133. The mask
cleaning chamber 1133 is connected to the mask shelf 1132 via gate
valve 1205. Accordingly, a vacuum tight sealing can be provided
between the mask shelf 1132 and the mask cleaning chamber 1133 for
cleaning of a mask. According to different embodiments, the mask
can be cleaned within the manufacturing system 1000 by a cleaning
tool, such as a plasma cleaning tool. A plasma cleaning tool can be
provided in the mask cleaning chamber 1133. Additionally or
alternatively, a further gate valve 1206 can be provided at the
mask cleaning chamber 1133, as shown in FIG. 10. Accordingly, a
mask can be unloaded from the manufacturing system 1000 while only
the mask cleaning chamber 1133 needs to be vented. By unloading the
mask from the manufacturing system, an external mask cleaning can
be provided while the manufacturing system continues to be fully
operating. FIG. 10 illustrates the mask cleaning chamber 1133
adjacent to the mask shelf 1132. A corresponding or similar
cleaning chamber (not shown) may also be provided adjacent to the
carrier buffer 1421. By providing a cleaning chamber adjacent to
the carrier buffer 1421, the carrier may be cleaned within the
manufacturing system 1000 or can be unloaded from the manufacturing
system through the gate valve connected to the cleaning
chamber.
[0109] A device such as an OLED display can be manufactured in the
manufacturing system 1000 as shown in FIG. 10 as follows. This is
an exemplary manufacturing method only and many other devices may
be manufactured by other manufacturing methods. The substrate can
be loaded into the substrate handling chamber 1100 via load lock
chamber 1120. A substrate pretreatment can be provided within the
pretreatment chamber 1130 and/or 1131 before the substrate is
loaded in the vacuum swing module 1160. The substrate is loaded on
a carrier in the vacuum swing module 1160 and rotated from a
horizontal orientation to a vertical orientation. Thereafter, the
substrate is transferred through the transfer chambers 610 to 615.
The vacuum rotation module provided in the transfer chamber 615 is
rotated such that the carrier with the substrate can be moved to
the deposition apparatus provided at the lower side of transfer
chamber 615 in FIG. 11. Further rotation steps of one of the vacuum
rotation modules in one of the transfer chambers and transfer steps
through one or more of the transfer chambers are in the following
omitted for ease of reference in the description of display
manufacturing according to this paragraph. In the deposition
apparatus an electrode deposition is conducted in order to deposit
the anode of the device on the substrate. The carrier is removed
from the electrode deposition chamber and moved to one of the
deposition apparatuses 200, which are connected to the transfer
chamber 610, both of which are configured to deposit a first hole
injection layer. The two deposition apparatuses connected to the
transfer chamber 610 can, for example, be alternatively utilized
for the deposition of a hole injection layer on different
substrates. The carrier is then transferred to the lower chamber
connected to the transfer chamber 612 (in FIG. 10), such that the
first hole transportation layer can be deposited by the deposition
apparatus 200 provided below the transfer chamber 612 in FIG. 10.
Thereafter, the carrier is transported to the deposition apparatus
200 provided at the lower side of transfer chamber 613 in FIG. 10,
such that a blue emission layer can be deposited on the first hole
transportation layer. The carrier is then transported to the
deposition apparatus connected at the lower end of transfer
chambers 614 in order to deposit the first electron transportation
layer. In a subsequent step, further hole injection layers can be
deposited, for example in the deposition apparatus provided at the
lower side of transfer chamber 611 in FIG. 10, before the red
emission layer can be provided in the deposition apparatus at the
upper side of transfer chambers 612, and the green emission layer
can be deposited in the deposition apparatus provided at the upper
side of transfer chamber 614 in FIG. 10. Further, electron
transportation layers may be provided between the emission layers
and or above the emission layers. At the end of the manufacturing,
a cathode can be deposited in the deposition apparatus provided
below the transfer chamber 615 in FIG. 10. According to yet further
embodiments, additionally one or more exciton blocking layers (or
hole blocking layers) or one or more electron injection layers may
be deposited between the anode and the cathode. After deposition of
the cathode, the carrier is transferred to the further vacuum swing
module 1161, wherein the carrier with the substrate is rotated from
the vertical orientation to a horizontal orientation. Thereafter,
the substrate is unloaded from the carrier in the further substrate
handling chamber 1101 and transferred to one of the thin-film
encapsulation chambers 1140/1141 for encapsulating the deposited
layer stack. Thereafter, the manufacturer device can be unloaded
through load lock chamber 1121.
[0110] In light of the above, the embodiments described herein can
provide a plurality of improvements, particularly at least one or
more of the below mentioned improvements. A "random" access to all
chambers can be provided for such systems using a vertical cluster
approach, i.e. systems having a cluster deposition system portion.
The system concepts can be implemented for both RGB and White on CF
deposition by offering flexibility in adding the number of modules,
i.e. deposition apparatuses. This flexibility could also be used to
create redundancy. A high system uptime can be provided by a
reduced or no need to vent the substrate handling or deposition
chambers during routine maintenance or during mask exchange. Mask
cleaning can be provided, either in-situ by optional plasma
cleaning or external by offering a mask exchange interface. A high
deposition source efficiency (>85%) and a high material
utilization (>50%) can be provided using a scanning source
approach with a 180.degree. turning mechanism to coat 2 or more
substrates alternatingly or simultaneously (source-train
configuration) in one vacuum chamber. The carrier stays in vacuum
or under a controlled gas environment due to an integrated carrier
return track. Maintenance and pre-conditioning of the deposition
sources can be provided in separate maintenance vacuum chambers or
source storage chambers. A horizontal glass handling, e.g.
horizontal atmospheric glass handling, can be more easily adapted
using already existing glass handling equipment of an owner of a
manufacturing system by implementing a vacuum swing module. An
interface to a vacuum encapsulation system can be provided. There
is a high flexibility to add modules for substrate inspection
(on-line layer analysis), mask or carrier storage. The systems have
a small footprint. Further, good scalability for current and future
glass sizes can be provided.
[0111] While the foregoing is directed to embodiments of the
invention, other and further embodiments of the invention may be
devised without departing from the basic scope thereof, and the
scope thereof is determined by the claims that follow.
* * * * *